Muscle Tone Flashcards
1
Q
Muscle Tone
A
- The amount of stiffness in a resting muscle/resistance offered by muscles to stretch or passive elongation (stiffness)
2
Q
Factors that influence muscle tone
A
- Body position & interaction of tonic reflexes
- Stress & anxiety
- Volitional effort and movement
- Medications
- General health
- Environmental temperature
- State of arousal or alertness (CNS)
- Fevers, infections, bladder fullness, pain, etc.
3
Q
Intrinsic stiffness causing muscle tone
A
Weak actin-myosin bonds
4
Q
Passive stiffness causing muscle tone
A
Titin
5
Q
Hypotonia
A
- Decreased resistance to passive movement/muscle being lengthened
- Decreased DTRs
6
Q
Flaccidity
A
- Complete loss of muscle tone
- Most severe form of hypotonia
- Seen after acute stroke, LMN injury, SCI, and alpha motor neuron disease (ALS)
7
Q
Hypertonia
A
- Abnormally strong resistance to passive stretch
- Two types: Spastic and Rigid
- Seen with UMN ONLY
8
Q
Dystonia
A
- Basal ganglia disorder
- Involuntary muscle contractions causing abnormal twisting movements or postures
- Worsened by stress, fatigue, and pain
- Movements make it more difficult to talk, but no impairments with speech centers
- Minimized/stopped with sleeping
9
Q
Populations that present with hypotonia
A
- Anterior horn cell pathology
- Partial peripheral nerve lesions
- Lesions of CNS: Spinocerebellar lesions, some types of developmental delays, some forms of cerebral palsy
10
Q
Important things to look out for with hypotonicity
A
- Joint dislocation/subluxation
- Balance issues
- Airway and swallowing
- Muscle atrophy can lead to contractures
- Skin issues
11
Q
Spastic Hypertonia
A
- Velocity dependent increase in tonic stretch reflexes (muscle tone) and exaggerated DTRs
- Clasp-knife reflex, clonus, or positive Babinski may be present
- Caused from lesion in descending motor pathways
12
Q
Clinical implications of spastic hypertonia
A
- High risk for developing contractures
- Skin integrity issues
- Joint subluxation
13
Q
Rigid hypertonia
A
- Velocity independent resistance to stretch that is increased on BOTH sides of a joint in agonists and antagonists throughout the range; DTRs normal
- Types: Cog wheel & lead pipe
- Seen with diseases of basal ganglia (Parkinson’s) and late stage Alzheimer’s
14
Q
Clinical implications of rigid hypertonia
A
- Difficulty initiating movement
- Range of motion & loss in muscle length
- Stiff trunk causes breathing issues
- Contractures
- Skin issues from weight loss
15
Q
Decorticate Rigidity
A
- Sustained contracture & posturing where trunk and LE are in extension and UE in flexion with clenched wrists and fingers
- Occurs in lesions above middle of midbrain; damage to corticospinal tract
16
Q
Decerebrate Rigidity
A
- Sustained rigid muscle contractions and posturing of the trunk and limbs in full extension
- Lesions below the middle of the midbrain, usually at brainstem
- Worse prognostically than decorticate rigidity
17
Q
Opisthotonic Rigidity
A
- Body is held in abnormal posture involving rigidity and severe arching of the back, with the head thrown backwards
- More common in infants (with high fever, meningitis, encephalitis) and more exaggerated in adults with immature CNS (CNS vasculitis, encephalitis, meningitis)
18
Q
Clinical Examination of Muscle Tone
A
- Observation of resting posture/alignment
- Passive movement testing (tonic stretch reflexes)
- Active movement tests
- Palpation
- Postural control
19
Q
Modified Ashworth Scale
A
0 = no increase in muscle tone 1= slight increase in muscle tone manifested by catch or release or by minimal resistance at the end of ROM 1+ = slight increase in muscle tone, manifested by catch & release followed by minimal resistance throughout remainder of ROM 2 = More marked increase in tone through most of the ROM but affected part can still be moved 3 = Considerable increase in tone; passive movement throughout the ROM 4 = Affected parts held rigidly in place
20
Q
Treatments of Abnormal Tone
A
- Medical Management
- Surgical Management
- Physical interventions (PT)
